此处的问题与passwordreset()函数有关，

The issues here is with passwordreset() function ,

它应该看起来像这样:

passwordreset(): Promise<any> {
  // this should return a promise
  // make sure , you are returning promise from here
  return this.http.get(url)
             .toPromise()
             .then(response => response.json().data)
             .catch(this.handleError);
}

您正在返回promise函数中的promise，但是没有返回 从passwordreset()返回它，

You were returning the promise inside promise function , but not returning it from passwordreset(),

请查看您的代码和更新后的代码，您将获得一个想法

Please have a look at your code and updated code , you will get an idea

您的代码:

passwordreset(email)
{ 
        var promise = new Promise((resolve,reject)=>{ 
            firebase.auth().sendPasswordResetEmail(email).then(()=>{ 
                            resolve({success :true}); 
                            })
                            .catch((err)=>{ 
                                reject(err); 
                            }) 
                            return promise; 
        }); 
}

更新的代码:

passwordreset(email): Promise<any>
{ 
        return new Promise((resolve,reject)=>{ 
            firebase.auth().sendPasswordResetEmail(email).then(()=>{ 
                                resolve({success :true}); 
                            })
                            .catch((err)=>{ 
                                reject(err); 
                            }); 
        }); 
}